1) 7x + 2 = 3x + 2
Subtract 3x from both sides.
4x + 2 = 2
Subtract 2 from both sides.
4x = 0
Divide both sides by 4.
x = 0
2) 3(2x - 4) = 2x + 5
Multiply everything in the parenthesis by 3.
6x - 12 = 2x + 5
Add 12 to both sides.
6x = 2x + 17
Subtract 2x from both sides.
4x = 17
Divide 4 on both sides.
x = 17/4
3) 12 + 4(x + 1) = 3 - 12x
Multiply everything in the parenthesis by 4.
12 + 4x + 4 = 3 - 12x
Combine like terms.
16 + 4x = 3 - 12x
Add 12x to both sides.
16 + 16x = 3
Subtract 16 from both sides.
16x = -13
Divide 16 on both sides.
-13/16 = x
4) 23x + 7 = 2 (15x - 14x) - 56
Solve what is in the parenthesis.
23x + 7 = 2 (x) - 56
23x + 7 = 2x - 56
Subtract 2x from both sides.
21x + 7 = -56
Subtract 7 from both sides.
21x = -63
Divide 21 on both sides.
x = -3
Hope this helps!